# OS_CancelAlarm

## C Specification

      #include <nitro/os.h>

      void OS_CancelAlarm( OSAlarm* alarm );

## Description

This function cancels an alarm. After the alarm has been cancelled, the alarm structure can be used for another alarm.

A periodic alarm that was activated by `OS_SetPeriodicAlarm` can cancel itself from within the alarm handler.

## Arguments

`alarm` | Pointer to the alarm structure to cancel

## Return Values

None

## See Also

`OS_InitAlarm`, `OS_CancelAlarms`, `OS_CancelAllAlarms`, `OS_SetPeriodicAlarm`

## Revision History

03/22/2004 Added that a periodic alarm can cancel itself
02/04/2004 Initial Version